Abstract: In terms of neutron activation source terms, the calculation and analysis of nuclide inventory are very important in reactor physics and source term analysis. Generally speaking, nuclides will be activated when materials are irradiated by neutrons. Calculation and analysis of nuclide inventory can provide data support for shielding design, safety accident analysis and structural material selection of nuclear power plants. Commonly used methods for calculation and analysis of nuclide inventory mainly include transmutation trajectory analysis, Taylor expansion method, Chebyshev rational approximation method, etc. The source term team of North China Electric Power University has developed a neutron source term activation calculation program ABURN with independent knowledge based on the activation calculation theory algorithm. The program currently includes groups of EAF-2007. Transmutation trajectory analysis can be selected for source term calculation. The program realizes functions such as neutron activation calculation, decay calculation, pulse calculation, uncertainty and sensitivity analysis, and nuclide track tracking and contribution statistics based on the transmutation trajectory analysis and so on. After the integrated development of the program function, a series of benchmark questions were tested and compared with the international authoritative source term calculation program FISPACT. In the decay example of ³⁹S, the maximum relative error between the ABURN result and the FISPACT result is 0.00%; in the activation example of Ti, the maximum relative error of the uncertainty analysis result is 0.18%; in the pulse calculation result of ⁵⁰Cr, the maximum relative error is −0.05%. These results demonstrate that the ABURN program calculates accurately and that all functions are correctly implemented.